The role of dermorphin in the regulation of the processes of hibernation in mammals.

Data are presented in this paper regarding the influence of the opioid peptide, dermorphin, and its conjugate on the conditioned reflex activity of sousliks. The administration of dermorphin (0.1 mu/g, subcutaneously) is accompanied by a fall in body temperature, slowing of the baseline vegetative indices, and the sinking of the animal into a sleep-like state. A substantial disturbance of conditioned reflex activity was identified in the late period (delayed effects). Immunization of the hibernating sousliks with a conjugate of dermorphin leads to a gradual awakening of the animals from hibernation, to the normalization of conditioned reflex activity, and to the appearance of the motoric component of a conditioned defense reaction. The question of a possible specific role of dermorphin in the mechanisms of hibernation is discussed.